Tag Archives: Pockett

CEMI vindicated?

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frogSo it turns out consciousness really is an electric buzz around the brain.

JohnJoe McFadden claims his conscious electromagnetic field information (CEMI) theory – which says that consciousness lies in the brain’s electromagnetic field – has now been borne out by a number of recent research findings. His paper is in the JCS, but a pdf can be accessed at Machines Like Us. We first discussed the CEMI theory eight years ago (can it really be that long?).

The case for CEMI is based in turn on the idea that synchronous neural firing can be shown to correlate with conscious awareness. Others have thought that lots of neurons firing in harmony at the right frequencies might be important of course; but the CEMI theory explains why it should be important by suggesting that synchronous firing produces effects in the endogenous magnetic field, which unsynchronised activity does not. If registering in that field is taken to be the same as presentation to consciousness we have a neat account of the phenomenon.

The first of the new studies quoted by McFadden, by Fujisawa et al, showed that fields of the kind generated by gamma oscillations in a slice of rat hippocampus affected the neuronal firing pattern. This demonstrates that neurons can influence each other significantly by electromagnetic means quite separate from ‘normal’ synaptic activity. The second, by Frohlich and McCormick, showed broadly similar influences of electromagnetic fields in the visual cortex of ferrets, supporting the claim that the endogenous fields provide a positive feedback loop that helps set up oscillatory networks. The third is research by Anastassiou et al which showed that neurons could influence each other through electric field effects: we discussed this ‘ephaptic coupling’ and pointed out its relevance to McFadden a couple of years ago (you read it here first, folks!).

So there’s the evidence; what does it actually mean? I think McFadden is right to claim that the evidence for electromagnetic field effects on neuron firing is now too strong to ignore. At a minimum, it’s something brain simulations will need to take into account. It’s likely, moreover, that rather than simply being a nuisance factor, it actually plays some functional role in how networks of neurons are recruited and operate together. Anything more?  McFadden suggests it may solve the binding problem; I’m not so sure. The binding problem is essentially the question of how information flows from different senses, processed at different speeds, with lags and gaps, somehow manage to end up in a smoothly coherent perception of reality with no jumps or lip-synch problems. Solving that problem may well involve bringing the activity of different neural assemblies together, but to me it’s not clear how field effects could do anything other than smoosh all the inputs together, which is almost the opposite of what we want.

Speculatively McFadden suggests the EM field might be doing field computing, whatever that may be. He quotes a bizarre finding from the School of Cognitive & Computing Sciences (COGS) group at the University of Sussex. They used an evolutionary approach to develop a network which could perform  a certain task, and then deleted the nodes which weren’t playing any part in the the final network.  Weirdly, they found that one of the essential nodes was not actually connected to anything; yet removing it made the network stop working; put it back and the network worked again. They concluded that electromagnetic coupling must be playing a part. Of course electromagnetic effects in a field-programmable gate array (the equipment used by COGS) are not particularly likely to be anything like electromagnetic effects in the radically different physical substrate of neuronal tissue, but it does illustrate the general principle.

I still don’t see that there are particularly good reasons to say that the EM field is the home of consciousness. For one thing consciousness is full of very complex content: while I can easily see how that complexity could be encoded in the fantastically complex patterns of neuron firing which go on in the cortex, it’s harder to think that the EM field has a sufficiently elaborate structure. My consciousness is (in places) quite sharply defined and multi-layered, whereas a EM field seems more likely to provide a misty general glow. Perhaps the neurons provide the content and the EM field the subjectivity?

But one thing McFadden’s theory cannot be is a solution to the ‘Hard Problem’ of subjective experience; his electromagnetic consciousness is playing a vital functional role in the operation of the brain, whereas qualia, strictly defined, have no causal effects. So much the worse for the theory of qualia, you might think; that just helps show that Dennett was right and the whole business of qualia is nonsensical. However, Sue Pockett, whose electromagnetic theory of consciousness is a kind of cousin of McFadden’s, has jumped the other way on this, accepting that her own electromagnetic consciousness is epiphenomenal: it is produced by the brain but doesn’t in turn produce any effects of its own; consciousness is a mere observer. This enables her to stay in the game so far as the Hard Problem is concerned, but of course it lands her with a different set of problems.

Perhaps in another eight years things will look very different – I rather hope so.

 

Pockett redux

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Electric BrainSue Pockett is back in the JCS with a new paper about her theory that conscious experience is identical with certain electromagnetic patterns generated by the brain. The main aim of the current paper is to offer a new hypothesis about what distinguishes conscious electromagnetic fields from non-conscious ones; basically it’s a certain layered shape, with negative charge on top followed by a positive region, a neutral one, and another positive layer.

Pockett sets the scene by suggesting that there are three main contenders when it comes to explaining consciousness: the thesis that consciousness is identical with certain patterns of neuron firing; functionalism, the view that consciousness is a process; and her own electromagnetic field theory. This doesn’t seem a very satisfactory framing. For one thing it doesn’t do much justice to the wild and mixed-up jungle which the field really is (or so it seems to me); second there isn’t really a sharp separation between the first two views she mentions – plenty of people who think consciousness is identical with patterns of neuronal activity would be happy to accept that it’s also a neuronal process. Third, it does rather elevate Pockett herself from the margins to the status of a major contender; forgiveable self-assertion, perhaps, although it may seem a little ungenerous that she doesn’t mention that others have also suggested that consciousness is an electromagnetic field (notably Johnjoe McFadden – although he believes the field is causally effective in brain processes, whereas Pockett, as we shall see, regards it as an epiphenomenon with no significant effects).

Pockett mentions some of the objections to her theory that have come up. One of the more serious ones is the point that the fields she is talking about are in fact tiny and very local: so local that there is no realistic possibility of the field from one neuron influencing the activity of another neuron. Pockett is happy to accept this; conscious experience doesn’t actually have the causal role we usually attribute to it, she says: it’s really just a kind of passenger accompanying mental processes whose course is determined elsewhere. She cites various people in support of this epiphenomenalist view, including Libet – she has some interesting things to say about his experiments (but doesn’t note that he too liked the idea of a mental field of some kind).

The new thesis about the shape of conscious fields appears to spring from observation of neuronal structure in the neocortex, and in particular the fact that in its fourth layer there are no pyramidal cell bodies. This is a feature which appears to be characteristic of the parts of the neocortex often associated with consciousness, and it implies that there is a gap or neutral region in the fields generated there, helping to yield the layered structure mentioned above. Pockett proposes a number of experiments which might support her view, some of which have already been carried out.

So what do we make of that? I see a number of problems.

First is the inherent implausibility of the overall theory. Why on earth would we identify conscious experience with tiny electromagnetic fields? I think the attraction of the theory comes from thinking about two kinds of consciousness, more or less the two kinds identified by Ned Block: the a-consciousness that does the work of useful, practical cogitation, and the p-consciousness which simply endows it with subjective feeling. Looked at from this angle it may be appealing to think that the actual firing of neurons is doing the a-consciousness while the subjectivity, the phenomenal experience, come from the subsidiary electric buzz.

But when we look at it more closely, that doesn’t make any particular sense. The problem is that conscious experience doesn’t seem like anything in physics, whether a field or a lump of matter. If we’re going to identify it with something physical, we might as well identify it with the neurons and simplify our theory – dropping the field entity in obedience to Occam’s Razor. Nothing about the electrical fields helps to explain the nature of phenomenal experience in a way that would motivate us to adopt them.

Second, there’s the problem of Pockett’s epiphenomenalism. Epiphenomenalism is very problematic because if consciousness does not cause any of our actions, our reports and discussions about it cannot have been caused by it either. Pockett’s own account of consciousness could not have been caused by her actual conscious experience, and nothing she writes could be causally related to that actual experience: if she were a zombie with no consciousness, she would have written just the same words. This is a bit of an uncomfortable position in general, but it also means that Pockett’s ambitions to test her theory experimentally are doomed. You cannot test scientifically for the existence of a supposed entity that has no effects because it makes no observable difference whether it’s there or not. All of Pockett’s proposed experiments, on examination, test accessible aspects of her theory to do with how the fields are generated by neurons: none of them test whether consciousness is present or absent, and on her theory no such experiment is possible.

While those issues don’t technically prove that Pockett is wrong, they do seem to me to be bad problems that make her theory pretty unattractive.

 

Electromagnetic

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Picture: Susan Pockett.
We have become used to hearing that novel theories of quantum mechanics might somehow account for consciousness. A theory which invokes only common or garden electromagnetism seems refreshingly simple by comparison – almost naively simple at first sight. But such is the hypothesis put forward by Susan Pockett in her book ‘The Nature of Consciousness’. The hypothesis can be briefly stated – ‘consciousness is identical with certain spatiotemporal patterns in the electromagnetic field’ .

The original inspiration for the theory apparently lies in the sense of cosmic oneness described in Hinduism and (rather an unexpected choice) Plato. Pointing out that the ancients had some handy ideas about atoms, Pockett suggests we could similarly look for ancestral wisdom as a starting point for an enquiry into consciousness. One possible clue, according to her, is that one can find in Hinduism (and Plato) the idea of a fundamental underlying unity, a universal consciousness. I don’t think anyone would have argued very much if she had claimed it was a common feature of mystical experience in virtually all religions, actually. This mystical element is clearly important to her, since it is brought back in to round off the book’s conclusion.

Bitbucket Oh great. Good to know we’re dealing with hard science again.

Well, actually we are. If you want scrupulous quotation of authoritative empirical evidence, you won’t be disappointed here. The theory may be mystically inspired, but being a practical New Zealander, brought up, as she says, to believe any problem can be solved with baler twine, Pockett quickly gives it a more concrete form. This universal consciousness, she asks – doesn’t that sound a bit like some kind of field? If consciousness were some kind of electromagnetic effect, it could be part of the universal electromagnetic field, and hence genuinely part of a cosmic unity. Now, you wouldn’t want it to lose its separate existence altogether, or even leak across to other people in the form of telepathy (at least, not obviously), but that’s OK. If we were talking about very low frequency fluctuations, in the 0-100 Hz range, they wouldn’t propagate very far and would remain pretty much isolated, barring the kind of jolt to the brain which would have significant physical effects in any case.

Is there any reason to think that the brain might work at this kind of frequency, and that if it does, that the relevant patterns vary in a way that matches the variation of conscious experience?

Before we can consider the match with conscious states, we need to be a bit clearer about the kind of consciousness we mean. Pockett is only talking about the kind of subjective, phenomenal consciousness we almost certainly share with animals – qualia, in fact, not articulate, decision-making, reflective consciousness. She identifies three different states of consciousness – waking, dreaming, and dreamless sleep – and suggests there might be grounds for accepting another – a half-way state between waking and sleep which she identifies with the kind of meditative trance mystics go in for. It appears that EEG evidence does indeed show various wave patterns at suitable frequencies for all three (or four) of these conscious states. So far so good.

The next step is to examine the evidence for covariance between these EEG patterns and conscious sensations. It’s characteristic of Pockett’s agreeably down-to-earth style that smell, for once, is tackled first and gets a fair share of the attention, along with hearing and vision. These chapters form an interesting survey in their own right, though the details don’t matter much from our point of view. Covariance turns out to be relatively easy to establish in simple organisms, but in human beings rather a lot of processing of the relevant data is required. Nevertheless, I think most people would be happy to accept the broad conclusion that there is, indeed, evidence for covariance in all three senses.

Covariance, of course, is not enough in itself to establish the truth of Pockett’s hypothesis. Most people, as she recognises, would be inclined to say that the relationship between conscious sensations and electromagnetic patterns is due to the fact that they both arise from the same patterns of neural activity. I don’t think Pockett has a knock-down argument against this one: essentially she thinks it is much easier to conceive of consciousness as ‘just being’ a shimmering electromagnetic field than ‘just being’ patterns of neural activity – she even seems to suggest that the latter view tends towards dualism – but I’m not convinced.

So why should we believe in the hypothesis? I think there are three main points. One is the ‘mystic unity’ argument. To find this appealing, you have to believe in some kind of cosmic unity of consciousness to begin with, of course. But even if you do, I’m not sure the theory backs it up as strongly as Pockett suggests. At one point she sums it up quite accurately by saying that the ‘spots’ of consciousness within the overall cosmic field are like the red spots on a spotted handkerchief, which, in a sense, confer the quality of redness on the handkerchief. But that doesn’t, except in a stretched or metaphorical sense, make it a red handkerchief or unite the spots in a handkerchief-wide redness. Pockett herself has to argue for isolation of individual consciousnesses in order to defend herself against suggestions that if her theory were true, we should all be telepathic, or disrupted by electromagnetic events around us. I don’t, ultimately, find myself tempted by Pockett’s suggestion that her ideas, similarly, mean that the Cosmos itself is conscious.

The second point is a claim that the theory solves the binding problem – how conscious experience appears unified although the data from different sense organs makes its way into the brain at different times. If everything feeds into a single overall electromagnetic pattern, unity is guaranteed. This is a tempting idea, and a real prize if it worked. I think in the final analysis it underrates what we already know about the importance of neural events to sensory experiences. Since the theory only deals with qualia-style consciousness, it also leaves us with a problem on our hands about how sensory data feed into the other, cogitative form of consciousness. Nevertheless, I don’t think the idea that electromagnetic effects are relevant here can be entirely dismissed.

The third, and most startling point is that if Pockett is right, it is possible in principle to recreate the patterns which constitute conscious experience without a brain at all. Conscious computers are the least of it – if this is right you can generate a conscious experience of, say, the colour orange, in empty space. Pockett presumes that if someone’s brain were moved to coincide with such a floating experience, the owner of the brain would indeed ‘have’ that experience. If Pockett could indeed find a practical way of ‘beaming’ chosen experiences into someone’s mind (without, presumably, the need to know any details about the particular brain involved) it would be a most dramatic vindication.

I’m not holding my breath, though – it just seems unlikely that the electromagnetic aspect of the brain could ever be so thoroughly divorced from the neural activity. This touches on a basic problem with the theory which comes out in a number of different ways. One of the objections discussed and dismissed in the book is that electromagnetic fields can’t do computation. Now, as a matter of fact I think the objection, as stated, is on dubious grounds anyway. It isn’t clear to me that the kind of consciousness under discussion – qualia, subjective experience – is meant, by those who espouse it, to be computational anyway. But there is, I think, a problem about causal relations in the electromagnetic theory. It seems a little odd to think of electromagnetic patterns causing other electromagnetic patterns without physical objects – neurons, in fact – playing a role somewhere. The implication is either that some compromise with the neural perspective is needed (I think there are a number of reasonable options along these lines), or that the kind of consciousness under discussion is epiphenomenal – has no causal relevance. This latter view is, of course, virtually the orthodox one among qualists, but it involves considerable difficulty.

Pockett herself published a paper in the JCS recently declaring for epiphenomenalism, though whether she means the (indefensible in my view) hard philosophical version, or the unproblematic psychological version is still, I think, open to discussion.

I’m not convinced, but pending the arrival of an electromagnetic conscious-experience-synthesising machine, I think the hypothesis at least remains among the small and praiseworthy company of ideas about consciousness which are rational, clear, and in principle testable.

Blandula Ah – excuse me, but doesn’t it miss the whole point of mystical religious experience (in a typically flat-footed Western materialist way) to explain it as being a lot of radio waves? Isn’t transcendence of the physical something to do with it…?